Modern aircraft are equipped with a large number of external access panels that are flush mounted so as to provide an aerodynamic, low drag surface when airborne. These external access panels conventionally allow access to, for example, hydraulic, electronic, and engine or engine systems. In order to maintain a panel in the closed position, while still providing quick access to the area behind the panel while the aircraft is parked on the ground, low-profile flush mounted latches of the over-center tension type typically are incorporated into the design of the panel for securing the panel to the aircraft frame. For example, see U.S. Pat. Nos. 4,743,052 and 6,343,815.
When the size of the panel exceeds a certain limit, there is a need to incorporate one or more shear pins into the panel as well. The shear pin maintains the structural rigidity of the panel in the closed position when twisting loads are present. Latches capable of supporting both tension loading and shear loading are known. For example, see U.S. Pat. No. 5,556,142 which describes a combination tension-shear latch of the rotary hook type. However, this rotary action is unsuitable for applications which must be flush mounted to panels with complex curvatures and is prohibitively large for smaller panel applications exhibiting minimal loading.
Furthermore, when an aircraft incorporates both over-center latches and shear pins, it is often difficult for one person to close the panel, as all the latches and pins must be aligned simultaneously. In a typical regional jet application, the access panels for the tailcone may incorporate two over-center latches and two shear pins, requiring the simultaneous alignment of four features to properly close the panel. In commercial aircraft having significantly larger panels, it is not uncommon to have six or eight features.
Accordingly, it is desirable to provide a dual action structural latch suitable for opposing tension and shear loads and which may be operated by one person. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.